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import java.applet.*;
import java.util.Date;
import java.awt.*;

public class Profile extends Applet
{
  TextArea output;

  private void println(String s)
  {
    output.append(s);
  }

  public void init()
  {
    int i,j;
    int x,y;
    Date t0,t1;

    // set up output window
    setLayout(null);
    output=new TextArea();
    output.setEditable(false);
    // set output to applet size
    output.setSize(getSize());
    add(output);
    System.gc(); // do garbage collection
    t0=new Date();
    // do enough to get a good time
    for (j=0;j<1000;j++)
      for (i=0;i<100000;i++)
      {            
        y=500-i;
        x=Math.abs(y); 
        // use math library
      }
    t1=new Date();
    elapsed("Math library",t1,t0);

    System.gc(); // do garbage collection

    t0=new Date();
    for (j=0;j<1000;j++)
    for (i=0;i<100000;i++)
    {
      y=500-i;
      x=y<0?-y:y; // compute yourself
    }
    t1=new Date();
    elapsed("Manual ABS",t1,t0);
        
    // set up for array test:
    int[] ary0;
    int[] ary1;
        
    ary0 = new int[100];
    ary1 =new int[50];
        
    System.gc(); // do garbage collection
    t0=new Date();
    for (i=0;i<500000;i++)
    {
      System.arraycopy(ary0,10,ary1,0,50);
    }
    t1=new Date();
    elapsed("arraycopy",t1,t0);

    System.gc(); // do garbage collection
    t0=new Date();
    // array takes more time
    // so less loops req'd
    for (i=0;i<500000;i++)
    {
      int q;
      for (q=10;q<60;q++) 
        ary1[q-10]=ary0[q];
    }
    t1=new Date();
    elapsed("Manual array",t1,t0);

    System.gc(); // do garbage collection
    t0=new Date();
    for (j=0;j<100;j++)
    for (i=0;i<5000000;i++)
    {
    int x1,q=10,z=4;
    x1=q*z;
    }
    t1=new Date();
    elapsed("Multiply by 4",t1,t0);

    System.gc(); // do garbage collection
    t0=new Date();
    for (j=0;j<100;j++)
      for (i=0;i<5000000;i++)
      {
        int x1,q=10,z=2;
        x1=q<<z;
      }
    t1=new Date();
    elapsed("Shift to multiply",t1,t0);
  }

  private void elapsed(String lbl,Date t1,Date t0)
  {
    long diff=t1.getTime()-t0.getTime();
    println(lbl +" : "+diff + "ms\n");
  }
}